ISSN:0031-9228    

DOI:10.1063/1.2405553

出版商:AIP    

年代:1905

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.1897506

出版商:AIP    

年代:1905

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.1897508

出版商:AIP    

年代:1905

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.1897510

出版商:AIP    

年代:1905

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.1897511

出版商:AIP    

年代:1905

数据来源: AIP

摘要:

In 1971, Mikhail Dyakonov and Vladimir Perel of the Ioffe Institute in Leningrad proposed a new transport phenomenon.1 If one applies an electric field to the ends of a semiconducting strip, they reasoned, electrons would scatter off impurities in a spin‐dependent way. As the electrons make their way along the strip, those with up spins would veer to one side, while those with down spins would veer to the other side.

ISSN:0031-9228    

DOI:10.1063/1.1897513

出版商:AIP    

年代:1905

数据来源: AIP

摘要:

These days it's easy to take information technology for granted: Our computers will do what they're programmed to do, the files we download will be intact, and compact discs and DVDs will deliver perfect sound and pictures. That trust is rooted in the pervasiveness of error correction: Errors inevitably creep in, through noisy transmission lines or scratches on CDs, but redundant coding of information and error‐correcting procedures minimize the effect of errors on downloading pictures or on our enjoyment of Bach cantatas.

ISSN:0031-9228    

DOI:10.1063/1.1897514

出版商:AIP    

年代:1905

数据来源: AIP

摘要:

After several months of controversy about claims that the Bush administration has politicized the makeup of science advisory panels to reflect the administration's policies, the National Academy of Sciences (NAS) has issued a report with recommendations that would ensure the president and federal agencies receive unbiased and complete science and technology advice. The report, the third academy study since 1992 on the role of science advisers in the federal government, focuses on two topics: the appointment process for the top S&T posts, including science adviser to the president; and the selection process used to appoint individuals to federal S&T advisory panels.

ISSN:0031-9228    

DOI:10.1063/1.1897515

出版商:AIP    

年代:1905

数据来源: AIP

摘要:

All the accelerators and storage rings at SLAC have been shut down since 11 October, when an electrical accident at the laboratory severely injured an electrician working for a subcontractor. SLAC director Jonathan Dorfan ordered the shutdown immediately after the accident, and he has decided that all experimental facilities should remain closed pending the findings of a Department of Energy accident‐investigation board and implementation of the remedies it mandates.

ISSN:0031-9228    

DOI:10.1063/1.1897516

出版商:AIP    

年代:1905

数据来源: AIP

摘要:

When James B. Garvin, NASA's newly appointed chief scientist, first spoke to PHYSICSTODAYlast month about President Bush's space vision of returning humans to the Moon, he was caught in afternoon rush‐hour traffic around Washington, DC. The Beltway traffic seemed like an apt metaphor for the surge of interest in lunar scientific and human exploration. After the initial rush of US and Soviet lunar programs in the 1960s and early 1970s, exploration was reduced to a few flybys by spacecraft on their way to the outer planets.

ISSN:0031-9228    

DOI:10.1063/1.1897518

出版商:AIP    

年代:1905

数据来源: AIP